Native Python in n8n Code Nodes

Python Code Node (native)

Since n8n 2.0 the Code node's Python runs as native Python in a task runner (language: "pythonNative"). The old Pyodide "Python (Beta)" is gone, and with it every n8n helper it had: _input, _json, _node, _now, _today and _jmespath all raise NameError now. Code copied from old templates, forum posts or older docs usually breaks on this.

JavaScript first — stronger than before

Native Python gives you two variables and plain Python, and by default no imports: no json, datetime or re. Everything n8n-specific ($('Node'), $jmespath, Luxon, this.helpers.httpRequest, static data) exists only in JavaScript. Use Python only when the user explicitly asks for it. Even then, first check whether an expression, Edit Fields, or a native node (Crypto, Date & Time, HTML, XML) does the job. See n8n-code-javascript and the transform gatekeeper in n8n-expression-syntax.

Quick start

# Run Once for All Items (default mode)
return [
    {"json": {"name": it["json"]["name"], "revenue": it["json"]["revenue"]}}
    for it in _items
    if it["json"].get("active")
]

# Run Once for Each Item
row = _item["json"]
return {"json": {**row, "name_upper": (row.get("name") or "").upper()}}

Node config: {"language": "pythonNative", "mode": "runOnceForAllItems" | "runOnceForEachItem", "pythonCode": "..."} on n8n-nodes-base.code typeVersion 2.

The only inputs: _items and _item

• Each variable exists only in its own mode. _items in each-item mode (or _item in all-items mode) raises NameError.
• Dict access only. it["json"]["name"] or it["json"].get("name"). it.json.name raises AttributeError: 'dict' object has no attribute 'json'.
• No other nodes. There is no _node / $('Node') equivalent. If you need data from another branch, bring it in with Merge first, or read it in JavaScript.
• Webhook payloads are under ["body"]: _items[0]["json"].get("body", {}).get("email").
• Binary data isn't covered here. Read and write binary in JavaScript (see n8n-binary-and-data).
• pairedItem: returning _items / _item keeps it. When you build new dicts and downstream uses $('Node').item, add "pairedItem": {"item": i} to each returned item. That isn't verified on native Python yet, so test-run before relying on it.
• Missing keys: prefer .get(key, default). row["missing"] raises KeyError.

Migration table for legacy code:

Imports: blocked by default

Every import (standard library and third-party) is checked against an allowlist before the code runs. The default allowlist is empty, so even import json rejects the whole node:

Security violations detected
Line 1: Import of standard library module 'json' is disallowed. Allowed stdlib modules: none

• n8n Cloud: no imports at all.
• Self-hosted: the admin can allowlist modules in the task-runner config (see n8n-self-hosting → TASK_RUNNERS.md). Some instances therefore allow json, datetime and re, and most don't.
• Default to import-free code. If an import would really help, confirm it first: a one-line test node import json + return [{"json": {"ok": True}}], or ask the user. Never assume.
• Without imports: parse JSON strings upstream ({{ JSON.parse($json.payload) }} in Edit Fields). Do date math in expressions (Luxon) or JS. ISO-8601 strings still compare and sort correctly as plain strings. Use the Crypto node for hashing.
• requests, pandas and numpy are never available unless the admin built a custom runner image. Use the HTTP Request node for HTTP.

Sandbox limits (these fail even without imports)

Everything else in plain Python works (verified): comprehensions, generators, lambdas, closures, recursion, try/except, f-strings / .format() / %, sorted/min/max/sum/any/all/ enumerate/zip/round, sets, isinstance, print() (output goes to the browser console).

Return shapes (verified)

Observed on n8n 2.38.5. The auto-wrapping and passthrough behaviours below are undocumented and could change in a later release. Re-check with a test run after upgrading n8n.

Run Once for All Items

Run Once for Each Item

Value conversion on output: tuple becomes a list, set becomes the string "{1, 2}", and a datetime becomes str(dt) ("2026-09-16 10:18:00.025792", not ISO). Convert explicitly (sorted(s), dt.isoformat()).

Prefer the explicit [{"json": ...}] in all-items mode and {"json": ...} in each-item mode. The auto-wrapping works, but the explicit shape makes the intent obvious to the next reader.